Microsoft began accepting testers in late April, and is now asking for more testers to apply for the beta via the registration page so that the company can "process the pool of participants for the second batch of invites to the ads trial program shortly." The program is the first time a Windows Live service that gives access to the Microsoft adCenter Publisher platform has been opened to developers. The selected participants will become adCenter Publisher account holders, as the account provisioning into the ads platform is done directly when they decide to enable ads in their SLS-based video playback options.

US testers who fill out a W-9 form have the opportunity to make money from their videos with this pilot program. The video content uploaded to Silverlight Streaming plays back with contextual ads relevant to the playback experience, based on keywords provided. A concept design is available (notice the "Want extra money?" banner with an embedded URL) on the SLS homepage.